We Marvel At Marvell - Crucial M550 SSD

In the face of increasingly stout competition, Crucial has again put their faith in a Marvell controller to power their latest flagship drive. Marvell hasn't had the fastest SSD controllers in the past and was often left on the sidelines with many manufacturers favoring parts from Indilinx, Samsung, Intel and SandForce instead. However, they've always been dependable and we've seen their performance improve substantially as of late so we were extremely eager to get Crucial's new M550 drive powered by the Marvell 88SS9187 controller on our test bench. We won't give away all the goods in the first paragraph but suffice it to say that we were duly impressed with the results.

The new M550 is an improvement upon the current M500 drive and will not replace the latter but rather sit alongside it in their product offerings. The M550 becomes the enthusiast performance drive while the M500 will remain as available for those seeking more of a balance between price and performance. Aptly enough, the M550 is rated to reach read speeds of 550MB/s and writes of up to 500MB/s with impressive IOPS numbers of 95k and 85k read/writes respectively. This is quite a large jump up from the M500 which capped out at 500MB/s reads and 400MB/s writes. The improved performance comes from the newer Marvell 88SS9189 controller with custom firmware and an implementation of what they term RAIN (Redundant Array of Independent NAND) which uses the NAND like a RAID PC uses multiple drives. Therefore, no compression techniques are used (à la SandForce), nor does it rely on caching to boost performance.

The Crucial M550 SSD Series will be available in the traditional 2.5-inch form factor with a 7mm z-height (9.5mm with adapter) in capacities ranging from 128GB to 1TB. There will also be mSATA and M.2 drives available in 128GB, 256GB and 512GB capacities. Launch day pricing and model numbers for the 2.5" drives are as follows:

In addition to performance, the amount of over-provisioning has been altered to allow the user a bit more usable space (i.e. 512GB rather than 480GB). The overall exterior design and branding has altered very little with the lighter blue of the M500 being darkened with more blacks on the M550. However, like people, it's what's on the inside that counts.

Crucial M550 512GB Internals

Four diminutive screws are all that holds the backplate on the Crucial M550 drive. Fortunately for us, there was only one small void sticker over a screw and no other anti-intrusion features employed.

Four more screws hold the PCB and there's a thermal pad between the controller and the shell of the drive which sticks them together making it a little harder to remove.

The first side of the PCB contains only the NAND modules with eight total on this side.

The 20nm Micron MLC NAND chips on the 512GB drive is 128Gb in density whereas the smaller drives use 64Gb chips. They carry part number 3ZA2D NW386.

The flip side of the board also contains eight NAND modules for a total of 16 on the drive, along with the controller and cache chips.

The cache ship carries FBGA code D9RLT which corresponds to part number MT42L256M16D1. This is an LPDDR2 SDRAM part that has a capacity of 4Gb (512MB). This works in tandem with the Marvell 88SS9189 which is the next generation controller from the 88SS9187 that we saw on the M500. It handles all of the usual duties like TRIM and garbage collection along with wear-leveling tasks. It also supports AES 256-bit hardware encryption and is responsible for overseeing the RAIN (Redundant Array of Independent NAND) technology we discussed in the article opening.

Test System & Comparison Drives

All tests were performed on a fresh and up-to-date install of Windows 8 Pro x64 with no other applications running while using AHCI mode set through the BIOS. Synthetic Benchmarks were run with the OS loaded on a 120GB Corsair Force SSD. In between every test, the test drive was secure erased using an instance of Parted Magic. As such, all results should be indicative of optimal performance. All components were set to their default speeds and are listed below.

Since there are so many SSDs out there now with different controllers, we started a reference table of which controllers are used by each drive to help you compare results. Different controllers definitely perform differently and each has various strengths and weaknesses. Like CPU's, even identical drives will have variations in performance and part of that variance may be attributable to the NAND flash used. Since the tests of the drives listed have spanned different test benches and represent different interfaces, we have listed the most recent ones for easy reference.

CrystalDiskInfo 6.0.4 Readout:

For the Crucial M550 512GB drive, the readout on CrystalDiskInfo 5.2.0 shows that both NCQ and S.M.A.R.T. are enabled, as well as TRIM and the interface is confirmed at SATA III (6Gbps). This is a great free tool to see lots of detailed information about the drive such as the firmware version for which we are running the latest available at the time of testing – MU01, which is also printed on the back of the drive if you look closely.

Let's have a look at the performance with some synthetic benchmarks followed up by some real world tests.

ATTO & AS-SSD Benchmarks

ATTO v2.47

ATTO is one of the oldest drive benchmarks still being used today and is still very relevant in the SSD world. ATTO measures transfers across a specific volume length. It measures raw transfer rates for both reads and writes and places the data into graphs that can be very easily interpreted. The test was run with the default runs of 0.5KB through 8192KB transfer sizes with the total length being 256MB.

ATTO - Intel Z77 Platform:

Benchmark Results: While it doesn't take the top spot in any of the scores, it's darn close and the best performance we've seen from a Marvell controlled drive. Very solid.

AS-SSD (1.6.4237.30508) Benchmark - Intel Z77 Platform:

We have been running the AS-SSD Benchmark app for over some time now and found that it gives a broad result set. The programmer has worked very hard on this software and continues to make updates often so if you use it, show him some love and send him a donation. There are now three tests that are found within the tool and we'll show the results from two of them.

Benchmark Results: You can see that the performance of the M550 is much more well rounded than that of the M500 with writes not straying too far from the reads while posting an overall score that is second only to the Samsung 840 Pro.

Benchmark Results: The zero slope of the graph lines prove out that data compression plays no role in performance metrics.

CrystalDiskMark & Anvil IOPS

CrystalDiskMark is a small benchmark utility for drives and enables rapid measurement of sequential and random read/write speeds. Note that CDM only supports Native Command Queuing (NCQ) with a queue depth of 32 (as noted) for the last listed benchmark score. This can skew some results in favor of controllers that also do not support NCQ.

CrystalDiskMark 3.0.2 x64 - Intel Z77 Platform

Benchmark Results: Again we see a nice jump in performance from the M550 over the M500 in every aspect of the benchmark. Very competitive performance overall.

Anvil Storage Utilities 1.050 RC6- Intel Z77 Platform

Along with the move to a new platform, we decided to make a change in one of the benchmarks. There's a relatively new benchmark called Anvil Storage Utilities that is in beta but close to production. It's a very powerful tool that measures performance through a variety of tests which can be customized. Since some of the tests more or less duplicate what we get from other benchmarks we use already, we decided to use the IOPS (Input/Output Operations Per Second) testing on 4kb file sizes at a queue depth of 32. IOPS performance is something SSD makers tout quite a bit but we generally don't do a lot of IOPS testing because frankly a lot of users can't relate to IOPS metrics as well and it tends to be more meaningful to the enterprise/server crowd. Still, it is another performance indicator with relevance and while some drives post good MB/s numbers, their IOPS scores aren't always commensurate which this test will prove out.

Benchmark Results: The IOPS performance is perhaps the most impressive performance improvement over the M500 with results that are nearly double for both reads and writes. This is one of the few drives where we don't see a large disparity between the reads and writes.

Real World Copy & Boot Tests

File Copy Times Via Teracopy 2.27:

One of the most common operations performed on a PC is moving/copying files. Using a free application called Teracopy, we copied large numbers of two file types from one folder to another on the same drive. Teracopy allows us to objectively measure the time of transfer and using the same drive prevents other devices from tainting the outcome. The operation requires the drive to perform both sustained read and writes simultaneously. The first set of files is a 5GB collection of JPG's of variable size and compression levels with a few movie (.MOV) files thrown in for good measure since most cameras now take video as well as stills. The second is a collection of MP3 files of various sizes which totals 5GB collectively. These file types were chosen due to their wide use and mixture of file sizes and compression levels.

Benchmark Results: Excellent copy times for the M550 with a slight improvement over the M500 so we definitely see a real world performance increase.

Windows Boot Times Via BootRacer:

Windows start up/shutdown time is always something people are interested in and we haven't done it in a while because there was little variation with the majority of the SSDs. We recently began using an application called BootRacer to objectively measure the start up times of the drives. All of the instances of Windows were identical and freshly installed with only the video driver installed.

Benchmark Results: With Windows boot times, the variances are small for most SSDs but it's a good test to make sure there are no hiccups in performance as there are lot of reads/writes happening during boot. Certainly no complaints here.

Final Thoughts & Conclusions

When we peeked in the drive, we saw that there are 512GB (1GB byte = 1,000,000,000 bytes) of NAND present and after the units conversion, over-provisioning and Windows have their share, we are left with 476GiB logically (1GiB = 1,073,741,824 bytes). Compared to the Crucial M500, you pick up an additional 29GB of usable space due to reduced spare area. If this isn't enough for you then you can step up to the 1TB M550.

Crucial has done a super job with the M550. It's a marked improvement on the M500 and it now competes with the best SATA III drives on the market in overall performance. We measured the reads and writes maxed out at 561MB/s and 512MB/s respectively and most impressively the IOPS nearly doubled up on the M500 performance with reads reaching 99k IOPS and writes at 83k IOPS. Best of all, it didn't balk at incompressible data so we observed a very even and consistent performance against our suite of tests. The Marvell 88SS9187 controller with Crucial's custom firmware gets the job done. The RAIN (Redundant Array of Independent NAND) technology employed is an innovative way to boost performance without doing a lot of caching which can be a risky proposition.

The M550 will also be sold under the Micron moniker which is the OEM channel brand whereas Crucial is the consumer arm. The pricing of the consumer M550 is slated to roll out as outlined below. For the 512GB drive we tested, it comes out to be about $0.71 per usable GB which is a very good price point, especially for a large capacity drive.

It's important to also point out that in addition to the 2.5" drives, Crucial will be releasing the M550 in the mSATA and M.2 form factors as well, although we don't have pricing for those off-hand. Also, the M500 is still going to be available alongside the M550 with each being targeted to a slightly different demographic. All in all, we were impressed with the performance of the M550 and happy to see Marvell matching up to the other high-end controllers. For those looking for a high performance drive, Crucial has given you one more option from which to choose.

Legit Bottom Line: The M550 is very impressive in performance and features and gives Crucial a flagship drive that they can can feel confident about competing with just about any consumer drive in the industry.